Field of the Invention
The present invention relates to a laser light source module and a laser light source device, and more particularly, it relates to the laser light source device that includes the plurality of laser light source modules mounted therein and condenses and emits a plurality of laser light beams.
Description of the Background Art
In recent years, a laser processing machine and a video display device such as a projector using semiconductor laser light beams as light source that have been widespread require the laser light source in a smaller size producing a higher output. Thus, a laser light source module including a semiconductor laser array mounted therein has been developed, the semiconductor laser array having semiconductor laser elements disposed in an array. Moreover, a laser light source device that includes the plurality of laser light source modules mounted therein and condenses and emits laser light beams from the plurality of laser light source modules has been developed (for example, see International Patent Publication No. WO 2009/081470 and Japanese Patent Application Laid-Open No. 2011-243717).
International Patent Publication No. WO 2009/081470 discloses a stem on which a plurality of power supply lead pins are provided vertically, a heat sink mounted on the stem, a submount substrate, and a laser light source module bonded to a semiconductor laser array in which a plurality of laser elements are disposed in an array through a lead frame. The laser light source module is configured to supply, with current, the lead pins extending from the bottom surface of the stem serving as a mounting surface and a cooling surface of the laser light source module to emit diverging light beams vertically to the bottom surface of the stem from the semiconductor laser array.
Japanese Patent Application Laid-Open No. 2011-243717 discloses a laser light source device in which a plurality of semiconductor laser arrays are disposed stepwise, laser light beams from each semiconductor laser array are collimated for both fast axis and slow axis, the fast axes alone are collectively condensed using a condensing lens, and the resulting light beams are optically combined into one by an optical fiber array composed of the same plurality of optical fibers arranged in the same pitch as the plural beams irradiated from the condensing lens.
However, in the technique of International Patent Publication No. WO 2009/081470, the diverging light beams are emitted vertically to the bottom surface of the stem serving as the mounting surface and the cooling surface of the laser light source module. Thus, in a case where the laser light source device (so-called spatial coupling laser light source device) that includes the plurality of laser light source modules mounted therein and condenses the laser light beams emitted from the laser light source modules is configured, it is difficult to reduce the gap between the laser light beam emitting portions even if the stems are disposed adjacent to each other. Therefore, a large-size condensing lens for condensing the laser light beams is needed, resulting in a problem that the laser light source device increases in size.
Furthermore, to collectively condense the laser light beams emitted from the plurality of laser light source modules, the collimator lens for accurately converting the diverging light beams emitted from each of the laser light source modules into parallel light beams is needed, and furthermore, each of the parallel light beams is needed to be parallel to each other with high accuracy, so that when each of the laser light source modules is disposed, the laser light source modules and the collimator lens require adjustments to be disposed, thereby resulting in complicated assembly and adjustments.
Moreover, in Japanese Patent Application Laid-Open No. 2011-243717, the same plurality of expensive optical fiber arrays in the same pitch as the plural beams are needed, and to condense the light beams to the optical fiber arrays, each of the semiconductor laser arrays and the collimator lens require highly accurate adjustments to the positions thereof to be fixed, thereby resulting in complicated assembly and adjustment operation. Furthermore, the semiconductor laser arrays fail to be disposed in the laser array arrangement direction, which prevents miniaturization and lower prices.